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CryptoHack

A free, fun platform for learning modern cryptography

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Learn By Doing

Learn about modern cryptography by solving a series of interactive puzzles and challenges. Get to know the ciphers and protocols that secure the digital world by breaking them.

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Level Up

Earn points by solving challenges. Finish categories to earn trophies and gain levels to track your progress. Can you reach the top of the scoreboard?

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Fresh Challenges

We are constantly creating new challenges to keep your crypto knowledge up to date. Expect exciting brainteasers and whole new categories as the site continues to grow.

New Challenges
ECLCG (HITCON CTF) CTF Archive 0
Sus (ImaginaryCTF) CTF Archive 0
Share (HITCON CTF) CTF Archive 0
Leet Universe (ImaginaryCTF (Daily)) CTF Archive 0
Hyper512 (HITCON CTF) CTF Archive 0
Weekly Top Users
#1 CommandMaster 6715
#2 sahuang 3675
#3 turboooooo 2680
#4 me2m8 2280
#5 L64 2090
Recent Solves
Finding Flags ShadowByte
Crossed Wires EOne
Deriving Symmetric Keys IITJ_72_Soumen
Passwords as Keys chrisdaboy
Greatest Common Divisor raw_dj
Recent Solutions
Extended GCD mpg 0
Signing Server strn 0
Broken RSA tonyfrg 0
Dancing Queen jergen85 0
CTRIME ispo 0

Level Up

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